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The skeleton of a bird.

The Skeleton of a Bird

The skeleton of a bird.

"Epipleurae.-- Thorax, scapular arch, and part of pelvic arch of a bobolink (Dolichonyx oryzivorus). ep, four epipleurae or uncinate processes of as many ribs; pl, pleurapophysial parts of seven ribs; hp, hemapopysial parts of six ribs; v, dorsolumbar vertebrae; st, sternum (the letters are on the carina or keel); m, manubrium sterni; cp, costal process of sternum, bearing f, furcula; ec, epiclidium of furcula; h, hypoclidium of fucula; gl, glenoid fossa, formed by coracoid and scapula; il, ilium; is, ischium; p, pubis; a, acetabulum." -Whitney, 1911

Bobolink Epipleurae

"Epipleurae.-- Thorax, scapular arch, and part of pelvic arch of a bobolink (Dolichonyx oryzivorus).…

"Entire skeleton of condor, showing the relative positions of the chief bones." -Thomson, 1916

Condor Skeleton

"Entire skeleton of condor, showing the relative positions of the chief bones." -Thomson, 1916

"Phalacrocorax bicristatus. Cormorant. The knee-joint of a Cormorants. F, femur; P, patella; T, tibia; Fb, fibula

The Knee-joint of a Cormorant

"Phalacrocorax bicristatus. Cormorant. The knee-joint of a Cormorants. F, femur; P, patella; T, tibia;…

"Phalacrocorax bicristatus. Red-Faced Cormorant. Skull showing sto, occipital style or nuchal bone; The style is somewhat tilted upward from its natural position." Elliot Coues, 1884

Cormorant Skull

"Phalacrocorax bicristatus. Red-Faced Cormorant. Skull showing sto, occipital style or nuchal bone;…

"Phalacrocorax bicristatus. Red-Faced Cormorant. Sternum and the shoulder from the skeleton of a Cormorant." Elliot Coues, 1884

Cormorant Sternum and Shoulder

"Phalacrocorax bicristatus. Red-Faced Cormorant. Sternum and the shoulder from the skeleton of a Cormorant."…

"Schizorhinal skull of curlew (top view), showing the long cleft, a, between upper and lower forks of each nasal bone." -Whitney, 1911

Curlew Skull

"Schizorhinal skull of curlew (top view), showing the long cleft, a, between upper and lower forks of…

"Fig 27. - Bones of the right wing of a duck, Clangula islandica, A, shoulder, omos; B, elbow, ancon; C, wrist, carpus; D, end of principal finger; E, end of hand proper, metacarpus. AB, upper arm, brachium; BC, fore-arm, antibrachium; CD, whole hand or pinion, manus; composed of CE, hand proper or metacarpus, excepting d2; ED, or d2, d3, d4, fingers, digits, digiti, h, humerus; rd, radius; ul, ulna; sc, outer carpal, scapholunare or radiale; cu, inner carpal, cuneiforme or ulnare; these two composing wrist or carpus. mc, the compound hand-bone or metcarpus, composed of three metacarpal bones, bearing as many digits - the outer digit seated upon a protuberance at the head of the metacarpal, the other two situated at the end of the bone. d2, the outer or radial digit, commonly called the thumb or pollex, composed or two phalanges; d3, the middle digit, of two phalanges; d4, the inner or ulnar digit, of one phalanx d2 is the seat of the feathers of the bastard wing or alula. D to C (whole pinion), seat of the flight feathers called primaries; C to B (fore-arm), seat of the secondaries; at B and above it in direction of A, seat of tertiaries proper; below A, in direction of B, seat of scapularies (upon pteryla humeralis), often called tertiaries. The wing shown half-spread: complete extension would bring A B C D into a right line; in complete folding C goes to A, and D to B; all these motions nearly in the plane of the paper. The elbow-joint and wrist are such perfect hinges, that, in opening or closing the wing, C cannot sink below the paper, nor D fly up above the paper, as would otherwise be the effect of the pressure of the air upon the flight-feathers. Observe also rd and ul are two rods connecting B and C; the construction of their joining at B and C, and with each other, is such, that they can slide lengthwise a little upon each other. Now when the point C, revolving about B, approaches A in the arc of a circle, rd pushes on sc, while ul pulls back cu; the motion is transmitted to D, and makes this point approach B. conversely, in opening the wing, rd pulls back sc, and ul pushes on cu, making D recede from B. In other words, the angle A B C cannot be increased or diminished without similarly increasing or diminishing the angle B C D; so that no part of the wing can be opened or shut without automatically opening or shutting the rest..." Elliot Coues, 1884

The Bones of the Right Wing of a Duck

"Fig 27. - Bones of the right wing of a duck, Clangula islandica, A, shoulder, omos; B, elbow, ancon;…

"Fig. 28. - Mechanism of elbow-joint. ..., where rc and uc show respectively the size, shape, and position of the radial condyle and ulnar condyle of the humerus. It is evident that in the flexed state of the elbow, as shown in the middle figure, the radius, rd, is do pushed upon that its end projects beyond ul, the ulna; while in the opposite condition of extension, shown in the lower figure, rd is pulled back to a corresponding extent." Elliot Coues, 1884

Mechanism of the Elbow-Joint

"Fig. 28. - Mechanism of elbow-joint. ..., where rc and uc show respectively the size, shape, and position…

"Skeleton of the trunk of a Falcon. Ca, coracoid, which articulates with the sternum (St) at ; Cr, keel of sternum; Fu (Cl), furcula (clavicles); G, glenoid cavity for humerus; S, scapula; Un uncinate process; V, vertebral, and Sp, sternal, portion of rib. (From Wiedersheim.)" A. H. Evans, 1900

The Skeleton of the Trunk of a Falcon

"Skeleton of the trunk of a Falcon. Ca, coracoid, which articulates with the sternum (St) at ; Cr, keel…

"Mature stapes of fowl, about x4; after Parker. st, its foot, fitting fenestra ovalis; mst, main shaft, or medio-stapedial element; sst, supra-stapedial; est, extra-stapedial; ist, infra-stapedial, its end representing a rudimentary stylo-hyal; f, a fenestra in the extra-stapedial." Elliot Coues, 1884

The Ear Bone of Fowl

"Mature stapes of fowl, about x4; after Parker. st, its foot, fitting fenestra ovalis; mst, main shaft,…

"Fig. 62 Skull of common fowl, enlarged. from nature by Dr. R.W. Shufeldt, U.S.A. The names of bones and some other parts are printed, requiring no explanation; but observe the following points: The distinction of none of the bones composing the brain-case (the upper back expanded part) can be found in a mature skull. The brain is contained between the occipital, sphenoidals, squamosals, parietals and part of frontal; the ethmoidals belong to the same group of cranial bones proper. All other bones, excepting the three otic ear-bones, are bones of the face and jaws. The lower jaw, of five bones, is drawn detached; it articulates by the black surface marked articular with the prominence just above- the quadratic bone. Observe that from this quadrate a series of bones quadrato-jugal, jugal, maxillary-makes a slender rod running to the premaxillary; this is the zygoma, or jugal bar. Observe from the quadrate also another series, composed of pterygoid and palatine bones, to the premaxillary; this is the pterygo-palatine bar; it slides along a median fixed axis of the skull, the rostrum, which bears the loose vomer at its end. The under mandible, quadrate, pterygoid, and vomer are the only movable bones of this skull. But when the quadrate rocks back and forth, as it does by its upper joint, its lower end pulls and pushes upon the upper mandible, by means of the jugal and pterygo-palatine bars, setting the whole scaffolding of the upper jaw in motion. This motion hinges upon the elasticity of the bones of the forehead, at the thin place just where the reference-lines from the words "lacrymal" and "mesethmoid" cross each other. The dark oval space behind the quadrate is the external orifice of the ear; the parts in it to which the three reference-lines go are diagrammatic, not actual representations; thus, the quadrate articulates with a large pro-otic as well as with the squamosal. The great excavation at the middle of the figure, containing the cirlet of the unshaded bones, is the left orbital cavity, orbit, or socket of the eye. The mesethmoid includes most of the background of this cavity, shaded diagonally. The upper one of the two processes of bone extending into it from behind is post-frontal or sphenotic process; the under one (just over the quadrate) is the squamosal process. A bone not shown, the presphenoid, lies just in front of the oval black space over the end of basisphenoid. This black oval is the optic foramen, through which the nerve of sight passes from the brain-cavity to the eye. The black dot a little behind the optic foramen is the orifice of exit of a part of the trifacial nerve. The black mark under the letters "on" of the word "frontal" is the olfactory foramen, where the nerve of smell emerges from the brain-box to go to the nose. The nasal cavity is the black space behind nasal and covered by that bone, and in the oval blank before it. The parts of the beak covered by horn are only premaxillary, nasal, and dentary. The condyle articulates with the first cervical vertebra; just above it, not shown, is the foramen magnum, or great hole through which the spinal medulla, or main nervous cord, passes from the spinal column. The basioccipital is hidden, excepting its condyle; so is much of the basisphenoid. The prolongation forward of the basisphenoid, marked "rostrum," and bearing the vomer at its end, is the parasphenoid, as far as its thickened under border is concerned. Between the fore end of the pterygoid and the basisphenoidal rostrum, is the site of the basipterygoid process, by which the bones concerned articulate by smooth facets; further forward, the palatines ride freely upon the parasphenoidal rostrum. In any passerine bird , the vomer would be thick in front, and forked behind, riding like the palatine upon the rostrum. The palatine seems to run into the maxillary in this view; but it continues on to premaxillary. The maxillo-palatine is an important bone which cannot be seen in the figure because it extends horizontally into the paper from the maxillary about where the reference life "maxillary" goes to that bone. The general line from the condyle to the end of the vomer is the cranial axis, basis cranii, or base of the cranium. This skull is widest across the post-frontal; next most so across the bulge of the jugal bar." Elliot Coues, 1884

Skull of a Common Fowl

"Fig. 62 Skull of common fowl, enlarged. from nature by Dr. R.W. Shufeldt, U.S.A. The names of bones…

"F. Fibula; T, tibia, with a, its cnemial process, and P, large patella, of a grebe." Elliot Coues, 1884

Leg Bones of a Grebe

"F. Fibula; T, tibia, with a, its cnemial process, and P, large patella, of a grebe." Elliot Coues,…

"Fig. 29., from a young grouse (Centrocercus urophasianus, six months old), is designed to show the composition of the carpus and metacarpus before the elements of these bones fuse together: r, radius; u, ulna; s, scapholunar or radiale; c, cuneiform or ulnare; om, a carpal bone believed to be os magnum, later fusing with the metacarpus; z, a carpal bone, supposed to be unciform, later fusing with metacarpus; 8, an unidentified fifth carpal bone, which may be called pentosteon, later fusing with the metacarpus; 7, radial or outer metacarpal bone, bearing the pollex or outer digit, consisting of two phalanges, d and k; 9', principal (median) metacarpal bone, bearing the middle finger, consisting of the two phalanges, d', d"; 9, inner or ulnar metacarpal, bearing a digit of one phalanx, d'". The pieces marked om, z, 7, 8, 9,. all fuse with 9'. (From nature by Dr. R. W. Shufeldt, U.S.A.)."Elliot Coues, 1884

The Wing Bones of a Young Grouse

"Fig. 29., from a young grouse (Centrocercus urophasianus, six months old), is designed to show the…

"Pelvis of a heron (ardea herodias), nat. size, viewed from below; from nature by Dr. R.W. Shufeldt, U.S.A. dl, dorso-lumbar vertebrae to and including the last one, sc; below sc, for the extent of the large black spaces (opposite the arrow) are the true sacral vertebrae; us, urosacral vertebrae (opposite the five oval black spaces; Il, ilium; Is, ischium; P, pubis; ob, obturator foramen. The arrow flies into the acetabulum.

The Pelvis of a Heron

"Pelvis of a heron (ardea herodias), nat. size, viewed from below; from nature by Dr. R.W. Shufeldt,…

The Hesperornis regalis was an ancient bird of the Cretaceous Period.

Hesperornis Regalis

The Hesperornis regalis was an ancient bird of the Cretaceous Period.

"Ichthyornis victor and I. dispar, ...were small forms of about the size of a Partridge, with the habits and appearance, it is presumed, of Terns or Gulls. The head was extremely large in proportion to the remainder of the skeleton; the beak was long and pointed, with entirely separate rami to the mandible; the sharp teeth, fixed regularly in distinct sockets, were inclined backwards, and occupied the whole of the lower and at least the posterior half of the upper jaw; the keel of the sternum was large and broad; the dorsal and cervico-dorsal vertebrae were biconcave. the quadrate articulated to the skull by one knob,... the metatarsus was short and the whole foot small; a furcula was probably present; the wings were well developed, indicating great powers of flight; while the tail was comparatively short, and ended in a pygostyle." A. H. Evans, 1900

Skeleton Head of a Ichthyornis

"Ichthyornis victor and I. dispar, ...were small forms of about the size of a Partridge, with the habits…

"Ichthyornis, though the wings are well developed, with fused metacarpals, and the sternum is keeled, the vertebrae present the extraordinary primitive character of being biconcave." Elliot Coues, 1884. This bird is believed to come from the Cretaceous of North America and is a seabird."

Restoration of Ichthyornis

"Ichthyornis, though the wings are well developed, with fused metacarpals, and the sternum is keeled,…

The skeleton of a bird. Labels: a, radius and ulna; b, dorsal vertebrae; c, sacrum and pelvis; g, ploughshare bone; h, tibia; i, metatarsus; d, furculum; e, carina of the sternum; f, distal phalanx of pectoral limb.

Skeleton of a Bird

The skeleton of a bird. Labels: a, radius and ulna; b, dorsal vertebrae; c, sacrum and pelvis; g, ploughshare…

"Fig 56 - Axial skeleton, minus the skull, of an owl, Asio wilsonianus, life size; from nature by Dr. R.W. Shufeldt, USA. at, atlas; ax,axis; cv, cervical vertebrae; c, c', cervical ribs, or free pleurapophyses; dv, dorsal vertebrae, excepting the last one, which joins the sacrum; R, two of the six true ribs (pleurapophyses), whereof sr is sacral; u, one of the five uncinate processes or epipleura; cr, two of the six sternal ribs(haemapophyses), whereof the sixth floats; p, pelvic or sacral region of the spine, comprehending one dorsal, and several lumbar, sacral proper, and urosacral vertebrae; I ilium; Is, ischium; P pubis; a, acetabulum; in, ischio-iliac foremen; o, obturator foramen; clv, caudal or coccygeal vertebrae, whereof py is the pygostyle; s, scapula; ohs, os humero-scapulare; cl, clavicle; C, coracoid; S, sternum." Elliot Coues, 1884

Axial Skeleton

"Fig 56 - Axial skeleton, minus the skull, of an owl, Asio wilsonianus, life size; from nature by Dr.…

"Desmognathous skull of mallard duck, Anas boscas, nat. size, from nature, by Dr. R.W. Shufeldt, U.S.A. Letters before. In the "bound-palate" type, the vomer in either abortive, or so small that it disappears; when existing it is usually slender and tapers to a point in front; the maxillo-palatines are united across the median line, either directly or by means of ossification in the nasal septum; the posterior ends of the palatines and the anterior ends of the pterygoids articulate directly with the rostrum (as in schizognathism). This type is simply and perfectly exhibited by a duck in which the maxillo-palatine is a broad flat plate united with its fellow in mid-line; the oval sessile basipterygoid facets are far forward, opposite the very ends of the pterygoids." Elliot Coues, 1884

Mallard Duck Skull

"Desmognathous skull of mallard duck, Anas boscas, nat. size, from nature, by Dr. R.W. Shufeldt, U.S.A.…

"Fig. 114. -Skulls of Turdidae and Sylvicolidae, nat. size; after Shufeldt. A, Oroscoptes montanus; B, Sialia mexicana; C, Cinclus mexicanus; D, Siurus naevius. Observe likeness between A and B, at points marked c, c', l, l'; and between C and D, at points marked b, b,' d, d'." Elliot Coues, 1884

Bird Skulls

"Fig. 114. -Skulls of Turdidae and Sylvicolidae, nat. size; after Shufeldt. A, Oroscoptes montanus;…

"Fig. 31. - Ulna of Colaptes mexicanus, showing points of attachment of the secondaries. (Dr. R. W. Shufeldt, U. S. A.)." Elliot Coues, 1884

Red Shafted Woodpecker Ulna

"Fig. 31. - Ulna of Colaptes mexicanus, showing points of attachment of the secondaries. (Dr. R. W.…

"Skull of a Wild Duck (Anus boscas), from the side. ag, Angular; als, alisphenoid; ar, articular; bt, basitemporal; d, dentaryl en, external nostrils, e.o, exoccipital; eth, ethmoid; fr, frontal; j, jugal; lc, lacrymal; mx, maxilla; mx.p, maxillopalatine process; n, nasal, parietal; pg, pterygoid; pl, palatine; ps, presphenoid; px, premaxilla; q, quadrate; q.j, quadratojugal; s.ag, supra-angular; s.o, supraoccipital; sq, squamosal; ty, tympanic cavity; v, vomer; II, foramen for optic nerve; V, for trigeminal." (From Wiedersheim.)" A. H. Evans, 1900

Diagram of the Skull of a Wild Duck

"Skull of a Wild Duck (Anus boscas), from the side. ag, Angular; als, alisphenoid; ar, articular; bt,…